1. Field of the Invention
This invention relates generally to improvements in air filtration, and more particularly, but not by way of limitation, to improved fin structure for air filters having a centrifugal pre-cleaner stage.
2. Description of the Prior Art
It is well known in the prior art to provide air cleaner assemblies for internal combustion engines or the like which employ a cyclonic or centrifugal pre-cleaner stage prior to the introduction of the incoming air through the conventional paper filter element. In these assemblies, unitary molded plastic fin structures, of substantially cylindrical shape, are disposed about the cylindrical outer periphery of a conventional air filter element. These fin structures are further characterized by a plurality of circumferentially spaced, diagonal fins or vanes mounted on the cylindrical outer periphery thereof which extend across an annular space or chamber defined by the exterior of the filter element and the inner wall of the filter housing within which the filter element is mounted.
In the assembly of the prior art fin structures upon the corresponding filter elements, it is common for the molded plastic fin structures to crack or split in the event of misalignment between the fin structure and the filter element when the fin structure is forced over the end cap of the filter element. It is also virtually impossible to remove and reuse a prior art fin structure from a filter element upon which it as been assembled when the filter element must be renewed or replaced, thus increasing the cost of filter element replacement to the manufacturer and the consumer. It is also common for replacement filter elements, with prior art fin structures assembled thereto, to be mishandled between the manufacturer and time of installation in an air cleaner assembly to the extent that one or more fins may be broken from the filter element or, in more extreme cases, the fin structure may become split and thereby become permanently disengaged from the filter element, thus rendering the replacement filter element useless for its intended purpose.
The prior art fin structures are also relatively bulky to store in the manufacturer's warehouse thus increasing storage costs which cost increases must ultimately be borne by the consumer.
The various embodiments of the present invention overcome these deficiencies in the prior art and provide many advantages thereover.